It's almost definitely a 9 pin connector as on the later Apple II's (IIc, IIc Plus, IIGS), as all of the combo IBM/Apple joysticks that I've personally seen are. Combo joysticks like this generally came out late in the Apple II's lifespan (and far enough into the PC's that it was a viable gaming machine on par with the Apple II), so they generally have the 9 pin plug. The fact that it advertises PC AT support on the box means it's from 1984 at the earliest.

(Edit... aaand now I see the 1993 copyright date. Well, that pretty much confirms to me that it'll be the 9 pin plug.)

Yeah I forgot to mention it'll have the Y cable, but the IBM connector I believe was the same connector up until basically USB, so there's no reason to worry about that. It's only the Apple connector that changed (I think the original was 16 pin, later changed to a more standard DE-9 connector).

I do seem to recall big warnings on my joystick and in my joystick manual to make sure to have the switch set correctly. I think you can potentially do some damage if the switch is set incorrectly.

I have a Suncom combo joystick like this, although I like the design of this one better.

nah you wont cause damage they both use the same circuit internally, the difference is the resistor (its a single shot 555 timer so to achieve compatibility you just switch in some extra caps to make up the difference tween pc and apple II)

they probably overstate it to help with "but it dont werk, what a load of junk" reactions (it would work but just not right)